Bariatric/metabolic surgery or weight loss surgery (WLS) has become not only an increasingly utilized obesity treatment option when conventional lifestyle change methods (decreased caloric intake, increased activity levels) fail, but also a safe and medically effective treatment choice for severe obesity. Yet, despite an increase in the number of WLS procedures performed in the United States annually, and the fact that many people express interest in WLS, only about 50 percent of referred or eligible persons for WLS actually undergo the procedure. Furthermore, studies have documented Hispanics and non-Hispanic Blacks (NHB) are significantly less likely than non-Hispanic Whites (NHW) to complete WLS despite higher rates of both severe obesity and obesity-related comorbidities (e.g. type 2 diabetes, heart disease). Reasons for the ethnic group disparities in post-WLS weight loss and comorbidity resolution are largely unknown; the field has not explored the effects of ethnic-group specific beliefs, behaviors and traditions on either pre-operative WLS completion timeframe or post-operative weight loss and comorbidity outcomes. We will examine the short (6-month)-, mid (12-months)-, and long (24-months)- term effects of WLS patients? socioecological factors (social, cultural, clinical and other environmental-support) via the following aims: AIM 1. Identify the socioecological characteristics associated with the following four patient-determined WLS groups: (1) early-completers of WLS (< 3 months), (2) later-completers of WLS (>3 months but within 12-15 months), (3) non-completers of WLS because surgery was electively cancelled after being scheduled; and (4) non-completers due to no interest in WLS after receiving a medical referral. AIM 2. patients' socioecological factors (social, via the following aims: AIM 2. Determine how differences in Groups 1 and 2 relate to post- operative weight loss and comorbidity resolution at 6- 12- and 24-months post- WLS. AIM 3. Explore the mediating interactions on and moderating effect of ethnicity, WLS commitment group differences. intrapersonal, interpersonal, clinical and other environmental interactions on WLS commitment group differences. A combined statistical approach (2 stage) using the techniques of classification and regression trees (CART) and standard multiple regression analysis will be used to model the influences of the preoperative socioecological and demographic variables (including ethnicity) as discriminators of commitment/completion group membership (Aim 1), and to determine the relationship between group membership after adjustment for the pre-operative discriminators resulting from the CART solution and post-operative socioecological profile and the effect on weight loss (Aim 2).